Needle-actuating mechanism for hemstitching machines



July 16, 1929.

G. M. EAMES ET AL 2 Sheets-Sheet Filed Apfil 4, 1927 Ja/m 6219:7490.

Coin,

July 16, 1929. e. M. EAMES ET AL 1,721,072

NEEDLE ACTUATING MECHANISM FOR HEMSTITCHING MACHINES Filed April 4, 1927 2 Sheets-Sheet gwuento'a Geogyafilkm .hlm 6. Bilge Patented July 16, 1929.

UITED 'lATES l,?Zl,07Z

PATENT CFFICE.

GEORGE M. EAMES, OF BRIDGEPORT, AND JOHN C. BINGE, OF STRATFORD, CONNECTL CUT, ASSIGNORS TO THE SINGER MANUFACTURING COMPANY, OF ELEZABETE, NEVT JERSEY, A COBPCRATION OF NEW JERSEY.

NEEDLE-ACTUA'IING MECHANISM FOR I-IEMSTITCHING MACHINES.

, Application filed April 4,

This invention relates to improvements in needle-actuating mechanisms for sewing inachines and more particularly to needle-vibrating mechanisms for hemstitching machines. The primary object of the invention is to provide a construction which is durable at high speed operation and capable of maintaining the accuracy of operation essential in hemstitching machines producing acceptable work.

A. hemstitching machine in which the present improvement has been embodied has the usual cloth-plate and overhanging bracketarm terminating in a head in Which a needle bar is mounted for vertical reciprocation.

Pivotally mounted upon a supporting plate at the lower end of the needle-bar are a pair of needlecarriers from which project substantially vertically directed guide-rods, reciprocating vertically with the needle-bar and vibrated laterally in proper timed relation with respect to the reciprocations of the needle-bar in the production of a hemstitch seam.

The present invention resides primarily in the machanism employed for vibrating the guide-rods to thereby impart lateral movements to the endwise reciprocating needles. To this end, the guide-rods are slidingly mounted in swivel joints each carried by a crank-arm on arock-shaft journaled in the head of the overhanging bracket-arm of the machine, the two rock-shafts being disposed at substantially the same level and affording a durable support for the crank-arms. Adjustably secured upon the ends of the rockshafts projecting at the rear side of the bracket-arm head are actuating arms directed toward each other and having their free ends connected to separate links having a coaxial pivotal connection with an arm of an elbow lever also fulcrumed upon said bracket-arm head. The other arm of the elbow-lever is suitably connected with a reciprocatory pitman actuated from a cam on a counter-shaft and geared to the main shaft of the machine. By means of this construction, the needle-vibrating crank-arms are not only durably mounted, but they are individually actuated from a single pitman in a man} ner such as to obviate the transmission of loose joint or other improper connections from one needle-vibrating crank-arm to the 1927. Serial No. 180,671.

other. A'further desirable feature of the present construction is that the disposition of the actuating mechanism described at the rear side of the overhanging bracket-arm removes from the operators direct vision a number of moving machine parts.

In the accompanying drawings, Fig. l is a rear side elevation of a hemstitching machine containing the present improved needleactuating mechanism. Fig. 2 is a sectional view substantially on the line 22 of Fig. 1. Fig.3 is-a front end elevation, partly in section, of the head of the machine bracket arm. Fig. 4c is a front side elevation of the bracket-arm head. Fig. 5 is a bottom plan view of a needle-carrier.

The hemstitching machine illustrated in the drawings has the usual framework including the cloth-plate 1 from which rises the hollow standard 2 of the overhanging bracket-arm 3 terminating in the head el. Journaled in suitable bearings provided in the overhanging bracket-arm is the rotary main shaft 5 carrying at one end the belt-pulley 6 and at its opposite end the crank-disk 7, connected in the usual manner by means of a link 8 with the needle-bar 9 journaled for vertical reciprocation in bearings provided in the head 4. The needle-bar 9 carries at its lower end a supporting plate 10 pivotally sustaining a pair of needle-carriers 11 and 12. The needle-carrier 11 comprises an apcrtured sleeve 13. supported for oscillation upon a shouldered pivot-bolt 14, passing through .an elongated aperture 15 provided in the plate 10 and secured upon said plate by means of a nut 16 and washer 17. As will be evident, this construction provides for a lateral adjustment of the pivot-axis of the needle-carrier upon the plate 10. Depending from the needle-carrier sleeve 13 is a split-clamp 18 for the shank of a needle 19 secured therein by means of a clamp-screw 20. Another splitclamp 21 integrally rising from the sleeve 13 is provided with an aperture 22 receiving the lower end of a substantially vertically disposed guide-rod 23, secured in said boss 21 by means of a clamp-screw 24. Needle-carrier 12 is similar to the described carrier 11 in construction and in its pivotal support. Clamped to the needle-carrier 12 is a needle 25 and a substantially vertically disposed guide rod 26, the supporting means for the needles and the auideurods being evidently such as to cause them to partake of the vertical reciprocations ot' the needle-bar.

In order to vibrate the needles laterally in the production of a hemstitch scam, the guiderods are connected with actuating mechanism constituting the principal feature of the present invention. The guide-rod 23 is received within a transversely apertured swivel-pin 27 mounted within a lateral boss 28 on the tree end of a crank-arm 29, disposed at the front of the braclietairnr head a and lined upon a roclt-shailt 30. The rock-shaft 30 has a substantially horizontal journal in a bushing til lined in a suitable aperture provided in said head 41., said roc -shat't projecti 11g beyond the rear face of the braclceharm head. Adjustably clamped by means of a screw 32 upon said projecting end ot the rock-shalt 30 is the split huh (iii an actuating arm 3-3, it being evident that the crauloarm 29, roe cshatt 30 and actuating; arm 33 constitute in etiect a bellcranlr-lever having; a substantial journal in the machine frame. The. guide-rod 26 is similarly connected with a swivel-s eeve within the boss on a cranlI-arn'i li -ted to a rock-shaft 3'? journaled in the head 3: and adjustahly carrying, at the rear side of said head. an actuating arm 38 equal in length to the arm 33. r

The arms 38 and 38 have their tree ends directed toward each other and are disposed substantially horizontal, said arms bein sepa rately connected by equal length links 39 4:0 with an arm 41 of anelbow-levertulcrumed upon a pivot-pin e3. disposed above the hori Zontal plane containing liflfl axes of the crankarms 38 and suitably fixed in the head l. The links 89 and have a coaxial pivotal. connection. with lateral projections 1-2 on the arm 11 of the elhowdever, whereby rocking movements of said elbow-lever will impart movements of equal extent to said arms 38 and therefore to t io needles through the described connections. In order to actuate the elbowlever, the other arm a l thereof is pivotally connected with one end of a horizontally disposed pitman 415 of which the opposite end is secured by a screw 46 within a transverse aperture provided in a swivel-pin 4:7 disposed within a lateral boss 48 of a slide-block d9. As customary, the boss 48 is formed with an elongated aperture 50 to provide clearance for the pitman e5, while the slide-hlocl: 49 is provided with an elongated aperture 51 entered by a screw adjustahly securing said slide-block to the vertically channeled face of a vibratory arm The arm 53 has an elongated huh journaled on a shaft 55 bridging the hollow standard 2 and lined in bushings 56 and 57, suitably secured in the machine trams and restraining the hub 54 against movement lengthwise ot' the shaft 55.

The vibratory arm 53 has an enlarged head 58 for sustaining the supporting stud 59 of a roller 60 positioned in a groove 61 of a rotary cam 62. Secured in the machine frame is a fixed shaft disposed below the mainsha'tt 5 and rotatably supporting the hub 64* of a gear G-il. The hub 6 t projects laterally from the gear (il to form a support upon which the cam 62 is fixed. The gear 64 meshes with a pinion (35 secured upon the main shaft the ratio of the pinion 65 and the gear 6 t being as l. to 3, whereby the needles each receive a complete vibration in the cycle of three sti ches co stituting a hemstitch figure.

any suitable mechanism complemental to the needles in the, formation of stitches may be employed, the present disclosure is confined for the suite of sinmlicity to the ncedle-actluiting mechanism described.

Having thus setiorth the nature of the invention, what we claim herein is:

1. In a hcmstitch sewing machine having a cloth-plate and an overhangling;- bracl a needle-actuating mechanism compri ing a reciprocatory needle-bar, a necdle carricr having a needle guide-rod pivotally supported upon said needle-bar, a cranl=;-arm operatively connected with said "aide-rod permitting endw e movements thereof and adapted to impartewise movements thereto, a substantially horizontal rock-shaft journaled in the bracket-arm carrying said crank-arm, an

actuating arm upon said 1' clr-shai t at the rear side of said bracket-arm, an elbow lever disposed at the rear side of said bracket-arm to rock upon a substantially horizontal axis shove the aXi s of said rock-shaft. a link connecting said lever with the rock-shaft actuating arm, a substantially horizontal pit'man disposed at the rear side of said, bracket-arm operatively connected with said lever, and means for reciprocating said pitman.

2. Needle actuating mechanism for two needle hemstitching machines, comprising areciprocatory needle-bar, a pair of needlecarriers having needle guide-rods pivotally supported upon said needle-bar, a pair of crank-arms operatively connected with said guide-rods permitting endwise movements thereof and adapted to impart sidewise movements thereto, a pair of rock-shafts carrying said crank-arms, actuating arms secured upon said rock-shafts, an actuating lever, linl: connections between said lever and each of the actuating arms, a reciprocatory pitman operatively connected with said actuating lever, and means for reciprocating said pitman.

3. Needle actuating mechanism for twoneedle hemstitching machines, comprising a reciprocatory needle-bar, a pair of needlecarriers having needle guide-rods pivotally supported upon said needle-bar, a pair of crank-arms operatively connected with said guide-rods permitting endwise movements thereof and adapted to impart sidewise movements thereto, a pair of rock-shafts carrying said crank-arms, actuating arms secured upon said rock-shafts, an actuating lever, a pair oi links having a coaxial pivotal connection with said lever and individually connected with said actuating arms, and means for actuating said lever.

4. Needle actuating mechanism for twoneedle hemstitching machines, comprising a reciprocatory needle-bar, a pair of needle carriers having needle guide-rods pivotally supported upon said needle-bar, a pair of bellcrank-levers each having one arm operatively connected with a needle-carrier guiderod permitting endwise movements of said guide-rods and adapted to impart sidewise movements thereto, an elbow-lever, means for actuating said lever, and a pair of links separately connected with the other arms of said bellcrank-levers having a coaxial pivotal connectionwith an arm of said elbow-lever.

5. Needle-actuating mechanism for twoneedle hemstitching machines, comprising a reciprooatory needle-bar, a pair of needlecarriers having needle guide-rods pivotally supported upon said needle-bar, a pair of bellcrank-levers each having one arm operatively connected with a needle-carrier guiderod permitting endwise moven'ients of said guide-rods and adapted to impart sidewise movements thereto, an actuating lever, means for actuating said lever, and a pair of links separately connected with the other arms of said bellcrank-levers having a pivotal connection with said actuating lever at one side of the fulcrum of the latter.

6. Needle-actuating mechanism for twoneedle hemstitching machines, comprising a reciprocatory needle-bar, a pair of needlecarriers having needle guide-rods pivotally supported upon said needle-bar, a pair of bellcrank-levers each having a substantially vertically directed arm operatively connected with a guide-rod to permit endwise movements of the rods and to impart sidewise swinging movements thereto, the other arms or" said bellcrank-levers being substantially horizontally directed toward each other, an actuating lever, means for actuating said lever, and separate links connecting said actuating lever with said substantially horizontal arms of the bellcrank-levers.

7. In a hemstitch sewing machine having a cloth-plate and an overhanging bracket-arm, a needle-actuating mechanism comprising a reciprocatory needle-bar, a pair of needlecarriers having needle guide-rods pivotally supported upon said needle-bar, a pair of crank-arms operatively connected with said guide-rods permitting endwise movements of the rods and adapted to impartsidewise swinging movements thereto, a pair of rockshafts journaled in said bracket-arm carrying said crank-arms, actuating arms carried by said rock-shafts at the rear side of said bracket-arm, an elbow-lever fulcrumed upon and disposed at the rear side of said bracketarm, separate link connections between said elbow-lever and said actuating arms, a pit man disposed at the rear of said bracket-arm for actuating said elboW-lev er, and a rotary cam for reciprocating said pitman to vibrate the needles in proper timed relationship with respect to the vertical reciprocations thereof.

In testimony whereof, we have signed our names to this specification.

GEORGE M. EAMES. JOHN C. RINGE. 

